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I. 
Cruise Report, RV ATAIR, Cruise 0671021-1, Bremerhaven - Thyboron —- Aberdeen, 18 Jul - 10 Aug 2023 
Underway Measurements 
A variety of routine underway measurements were carried out during cruise 067/021-1. Among 
the acquired data of interest were navigational information, near surface hydrography (temper- 
ature, conductivity, and thus salinity) measured by the vessel's thermosalinograph (TSG), 
near-surface fluorescence and turbidity obtained from a dual-wavelength ECO sensor attached 
to the TSG system, as well as meteorological parameters and water temperature recorded by 
the weather station operated by the German Weather Service (DWD) under the identifier 
CVTKCAL. Navigational and meteorological data was recorded from the beginning of the 
cruise on, recording of additional underway data was interrupted during the port stay in Thy- 
borgn, Denmark, and resumed afterwards. Data was logged in time steps of 1 sec by the 
vessel’s DSHIP system. All underway data relevant to this cruise were exported from the 
DSHIP database on a daily basis. Water depths were measured by a single-beam echo- 
sounder along the cruise track and on hydrographic stations. Depths provided by the vessel’s 
echo-sounding device result in water depths when the vessels’s draft of 5 m is added. Any 
further processing or quality control of water depth data was not carried out. 
7.1 Ship’s Meteorological Station 
The autonomous weather station installed aboard RV ATA/R and operated by the DWD auto- 
matically records every second all meteorological standard parameters like wind speed and 
direction, air temperature and air pressure, relative humidity and surface water temperature 
and others. While corresponding data is sent directly to the Global Telecommunication System 
(GTS), it is also fed into the DSHIP database. Figure 7.1 provides an overview on the meteor- 
ological conditions encountered during cruise 067/021-1. Raw data was smoothed by applying 
a moving median filter. Shortly before the port stay in Thyboren, Denmark, on 30 Jul 2023 after 
11:56 UTC, the DSHIP system showed an increasing number of missing values in the mete- 
orological and navigational data recording. After resetting the DSHIP system and restarting 
necessary drivers (31 Jul 2023), data quality was improved again. 
The average air temperature throughout the cruise was 14.9°C, but temperatures ranged from 
9.9°C to 24.1°C while at sea. Maximum water temperatures exceeded 20°C right at the start 
of the cruise, minum water temperatures were 11.7°C, the average was 16.6°C. Average air 
pressure was 1006.3 hPa, and pressures ranged from 992.8 hPa to 1019.8 hPa. Notable pe- 
riods of absolute wind speeds exceeding 7 Bf were observed on 25/26 July 2023, on 03/04 
August 2023, and between 07 and 09 August 2023. The average wind speed throughout the 
cruise was 8.14 m/s, which corresponds to a wind strength of 5 Bf. The maximum wind speed 
was 26.6 m/s, corresponding to 10 Bf. Figure 7.2 displays the spatial distribution of absolute 
wind speeds and directions (15 min average values) along the cruise track. The high wind 
speeds (> 9 Bf) caused by a pronounced storm system encountered off Norway near the end 
of the cruise finally resulted in the cancellation of the remaining station program.